-transparent.png){kind=logo}
We examined the intrinsic contractile performance of papillary muscles removed from the left ventricle of male and female Wistar rats. Muscles were studied isometrically and isotonically, stimulated at 0.1 Hz, perfused with Tyrode's solution having an external calcium concentration = 2.4 and maintained at 30 degrees C. In addition, we examined muscle response to changes in external calcium, added norepinephrine or verapamil and alterations in contraction frequency. No significant change in peak isometric development tension was observed between male and female preparations. However, muscles from male rats showed a significantly greater isometric time-to-peak tension and time to 1/2 relaxation with a depression of both the maximum rate of tension rise and maximum rate of tension decay. Isotonically, although peak shortening showed no difference between male and female preparations, the maximum velocities of shortening and relaxation were significantly depressed in muscles from male rats. Muscles from male animals also displayed significant prolongation of the time-to-peak shortening and time-to-peak velocity of shortening. These differences in papillary muscle performance were found over a wide range of muscle lengths, stimulus frequencies and bath concentrations of calcium, norepinephrine and verapamil. Thus differences in the intrinsic contractile performance between papillary muscle from male and female rats have been characterized.
J M Capasso, and
R M Remily, and
R H Smith, and
E H Sonnenblick
September 1970,
Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.),
J M Capasso, and
R M Remily, and
R H Smith, and
E H Sonnenblick
November 2000,
European journal of pharmacology,
J M Capasso, and
R M Remily, and
R H Smith, and
E H Sonnenblick
September 2007,
American journal of physiology. Endocrinology and metabolism,
J M Capasso, and
R M Remily, and
R H Smith, and
E H Sonnenblick
October 1994,
Transplantation proceedings,
J M Capasso, and
R M Remily, and
R H Smith, and
E H Sonnenblick
May 1987,
Brain research,
J M Capasso, and
R M Remily, and
R H Smith, and
E H Sonnenblick
March 2010,
Journal of the American College of Cardiology,
J M Capasso, and
R M Remily, and
R H Smith, and
E H Sonnenblick
July 1962,
New York state journal of medicine,
J M Capasso, and
R M Remily, and
R H Smith, and
E H Sonnenblick
July 2020,
Lancet (London, England),
J M Capasso, and
R M Remily, and
R H Smith, and
E H Sonnenblick
June 2024,
Expert review of cardiovascular therapy,
J M Capasso, and
R M Remily, and
R H Smith, and
E H Sonnenblick
March 2015,
Nursing and midwifery studies,
